An electrophotographic toner, namely a so-called electrostatic toner (sometimes also referred to a “toner” simply hereinafter), is used for developing a latent image, which has been formed by charging and exposure, to form a visible image in the electrostatic electrophotography. The toner is a charged fine powder in which a colorant such as carbon black or a pigment is dispersed in a resin. Such toners are broadly divided into a dry type two-component toner that is used together with a carrier such as iron powder or glass particles, a wet type toner that is in a disperse system using an organic solvent such as isoparaffin, a dry type one-component toner in which a magnetic fine powder is dispersed, etc.
By the way, an image obtained on a photoreceptor through the development with a toner is transferred onto paper, or an image directly developed on paper having a photosensitive layer formed thereon is fixed as it is by the use of heat or solvent vapor. Above all, fixing by a heating roller is a fixing method of contact type, so that this fixing method has high thermal efficiency, and even by a heat source of a relatively low temperature, an image can be surely fixed, and further, this method has advantages such as suitability for high-speed copying.
With spread of copy machines and printers in recent years, it is desired that the toners have a further improved image quality, in addition the toners are able to apply for high-speed printing, and toners have an excellent fixing property at low-energy. Therefore, toners having improved fixing property at low temperature are developed. For example, waxes of low melting points have been used (patent literatures 1 and 2) for the purposes of low temperature fixing of the toners.